There exists an vulnerability causing an abort() to be called in gRPC. The following headers cause gRPCs C++ implementation to abort() when called via http2:
te: x (x != trailers)
:scheme: x (x != http, https)
grpclb_client_stats: x (x == anything)
On top of sending one of those headers, a later header must be sent that gets the total header size past 8KB. We recommend upgrading past git commit 2485fa94bd8a723e5c977d55a3ce10b301b437f8 or v1.53 and above.
The product contains an assert() or similar statement that can be triggered by an attacker, which leads to an application exit or other behavior that is more severe than necessary.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Grpc | Grpc | 1.51.0 (including) | 1.53.0 (excluding) |
| Grpc | Ubuntu | bionic | * |
| Grpc | Ubuntu | kinetic | * |
| Grpc | Ubuntu | lunar | * |
| Grpc | Ubuntu | mantic | * |
| Grpc | Ubuntu | upstream | * |
| Grpc | Ubuntu | xenial | * |
While assertion is good for catching logic errors and reducing the chances of reaching more serious vulnerability conditions, it can still lead to a denial of service. For example, if a server handles multiple simultaneous connections, and an assert() occurs in one single connection that causes all other connections to be dropped, this is a reachable assertion that leads to a denial of service.